Refactor base64

implementations/javascript/packages/core/src/base64.ts

@@ -0,0 +1,46 @@
+const BASE64_DEC: {[key: string]: number} = {};
+[... 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'].forEach(
+    (c, i) => BASE64_DEC[c] = i);
+BASE64_DEC['+'] = BASE64_DEC['-'] = 62;
+BASE64_DEC['/'] = BASE64_DEC['_'] = 63;
+
+export function decodeBase64(s: string): Uint8Array {
+    const bs = new Uint8Array(Math.floor(s.length * 3/4));
+    let i = 0;
+    let j = 0;
+    while (i < s.length) {
+        const v1 = BASE64_DEC[s[i++]];
+        const v2 = BASE64_DEC[s[i++]];
+        const v3 = BASE64_DEC[s[i++]];
+        const v4 = BASE64_DEC[s[i++]];
+        const v = (v1 << 18) | (v2 << 12) | (v3 << 6) | v4;
+        bs[j++] = (v >> 16) & 255;
+        if (v3 === void 0) break;
+        bs[j++] = (v >> 8) & 255;
+        if (v4 === void 0) break;
+        bs[j++] = v & 255;
+    }
+    return bs.subarray(0, j);
+}
+
+const BASE64_ENC = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
+
+export function encodeBase64(bs: Uint8Array): string {
+    let s = '';
+    let buffer = 0;
+    let bitcount = 0;
+    for (let b of bs) {
+        buffer = ((buffer & 0x3f) << 8) | b;
+        bitcount += 8;
+        while (bitcount >= 6) {
+            bitcount -= 6;
+            const v = (buffer >> bitcount) & 0x3f;
+            s = s + BASE64_ENC[v];
+        }
+    }
+    if (bitcount > 0) {
+        const v = (buffer << (6 - bitcount)) & 0x3f;
+        s = s + BASE64_ENC[v];
+    }
+    return s;
+}

implementations/javascript/packages/core/src/bytes.ts

@@ -2,7 +2,8 @@ import { Tag } from './constants';
 import { GenericEmbedded } from './embedded';
 import { Encoder, Preservable } from './encoder';
 import { Value } from './values';
-import { Writer, PreserveWritable } from './writer';
+import type { Writer, PreserveWritable } from './writer';
+import { decodeBase64, encodeBase64 } from './base64';
 
 const textEncoder = new TextEncoder();
 const textDecoder = new TextDecoder();
@@ -51,6 +52,10 @@ export class Bytes implements Preservable<any>, PreserveWritable<any> {
         return new Bytes(Uint8Array.of(...bytes));
     }
 
+    static fromBase64(s: string): Bytes {
+        return new Bytes(decodeBase64(s));
+    }
+
     static fromHex(s: string): Bytes {
         if (s.length & 1) throw new Error("Cannot decode odd-length hexadecimal string");
         const result = new Bytes(s.length >> 1);
@@ -139,6 +144,10 @@ export class Bytes implements Preservable<any>, PreserveWritable<any> {
         return Bytes.isBytes(v) ? v : void 0;
     }
 
+    toBase64(): string {
+        return encodeBase64(this._view);
+    }
+
     toHex(digit = hexDigit): string {
         var nibbles = [];
         for (let i = 0; i < this.length; i++) {

implementations/javascript/packages/core/src/reader.ts

@@ -155,7 +155,7 @@ export class ReaderState {
             if (c === ']') break;
             acc = acc + c;
         }
-        return decodeBase64(acc);
+        return Bytes.fromBase64(acc);
     }
 
     requireDelimiter(prefix: string): void {
@@ -436,31 +436,6 @@ export class Reader<T> {
     }
 }
 
-const BASE64: {[key: string]: number} = {};
-[... 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'].forEach(
-    (c, i) => BASE64[c] = i);
-BASE64['+'] = BASE64['-'] = 62;
-BASE64['/'] = BASE64['_'] = 63;
-
-export function decodeBase64(s: string): Bytes {
-    const bs = new Uint8Array(Math.floor(s.length * 3/4));
-    let i = 0;
-    let j = 0;
-    while (i < s.length) {
-        const v1 = BASE64[s[i++]];
-        const v2 = BASE64[s[i++]];
-        const v3 = BASE64[s[i++]];
-        const v4 = BASE64[s[i++]];
-        const v = (v1 << 18) | (v2 << 12) | (v3 << 6) | v4;
-        bs[j++] = (v >> 16) & 255;
-        if (v3 === void 0) break;
-        bs[j++] = (v >> 8) & 255;
-        if (v4 === void 0) break;
-        bs[j++] = v & 255;
-    }
-    return Bytes.from(bs.subarray(0, j));
-}
-
 function isSpace(s: string): boolean {
     return ' \t\n\r'.indexOf(s) !== -1;
 }

implementations/javascript/packages/core/src/runtime.ts

@@ -1,4 +1,5 @@
 export * from './annotated';
+export * from './base64';
 export * from './bytes';
 export * from './codec';
 export * from './compound';

implementations/javascript/packages/core/src/writer.ts

@@ -4,6 +4,7 @@ import type { GenericEmbedded, Embedded, EmbeddedTypeEncode } from "./embedded";
 import { Encoder, EncoderState } from "./encoder";
 import type { Value } from "./values";
 import { NUMBER_RE } from './reader';
+import { encodeBase64 } from './base64';
 
 export type Writable<T> =
     Value<T> | PreserveWritable<T> | Iterable<Value<T>> | ArrayBufferView;
@@ -205,28 +206,6 @@ export class WriterState {
     }
 }
 
-const BASE64 = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
-
-export function encodeBase64(bs: Uint8Array): string {
-    let s = '';
-    let buffer = 0;
-    let bitcount = 0;
-    for (let b of bs) {
-        buffer = ((buffer & 0x3f) << 8) | b;
-        bitcount += 8;
-        while (bitcount >= 6) {
-            bitcount -= 6;
-            const v = (buffer >> bitcount) & 0x3f;
-            s = s + BASE64[v];
-        }
-    }
-    if (bitcount > 0) {
-        const v = (buffer << (6 - bitcount)) & 0x3f;
-        s = s + BASE64[v];
-    }
-    return s;
-}
-
 export class Writer<T> {
     state: WriterState;
     embeddedWrite: EmbeddedWriter<T>;